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Date: Thu, 29 Aug 2024 00:11:03 +0300 (MSK)
From: Alexander Monakov <amonakov@ispras.ru>
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Subject: Re: [musl] [PATCH] configure: prevent compilers from turning a * b
 + c into fma(a, b, c)


On Wed, 28 Aug 2024, Rich Felker wrote:

> I'm not clear on why the -mno-fused-madd would be needed. It should be
> a no-op with -ffp-contract=off unless __builtin_fma were called
> explicitly or something, no?

I think Glibc was applying it as a workaround for old GCC releases where
target backends were doing unrestricted contraction, or -ffp-contract=
option did not exist in the first place.

Alexander